During the evaluation or production of a hydrocarbon well, it is necessary to monitor various parameters for example the relative volumetric flow rates of the different phases (e.g. oil, gas and water) of the multiphase fluid mixture flowing into the pipe of the well from the hydrocarbon bearing zones, and/or to identify the phases.
Optical analysis probes that are used within a downhole measuring tool operate in harsh environment, namely extreme conditions including high pressure from several hundred bars up to 2000 bars, high temperature up to 200° C., presence of corrosive fluids such as sulfuric acid, presence and contamination by solid particles such as scales, asphaltenes, sand particles, as well as multiphasic flow conditions (oil, gas, water). Furthermore, there is the high shocks environment associated to wireline or drilling or production logging operations.
During an evaluation operation or a production operation, the optical tip of the optical analysis probe may be damaged. Further, the technologies associated with the optical tip may evolve. There is a need to ease the replacement of the optical tip.
The document WO2015059380 describes an optical probe comprising an optical guide; a sleeve surrounding the optical guide; a tapered sapphire tip, with a circular base, mounted at one end of the optical guide; a linking tube into which the tip is inserted and from which the latter projects by the two ends thereof; and a cylindrical body into which the tube is inserted, one end of which is inserted into a sheath arranged at one end of the sleeve.
This optical probe describes a particular assembly for securing in a watertight manner the tapered sapphire tip to the probe. This results in a complex assembly that is difficult to dismantle in case a replacement of the tapered sapphire tip is necessary.